1975 mercury 200 hard to pull

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paradactal

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Location
Modesto, Ca
I have a 1975 mercury 200 20 go that I picked up along with a 1979 evinrude 6hp all for $75. Garage kept on stands but haven't ran in 10 years. The mercury seems very hard to pull. A ton Of compression. Feels like the pistons may be a little dry on the inside. Can I pour oil or any other solution to lube it up? It just feels like it needs a little help. Any ideas?
 
If it were me, I would pull the spark plugs and spray oil into the cylinders and then turn it over slowly by hand to work the oil in.
Don't use WD40 it's too light weight, something like Triflow would work better.
 
I'll try that. I want to hit it with sea foam but I don't think my neighbors would like me smoking out the neighborhood. I'll just run it in my gas so it won't be as bad
 
Leave the spark plugs out when you work in the oil. Will give you a better idea if the stiffness is coming from the compression/pistons or else where in the motor.
 
So I'm not a boat mechanic, but can somebody just kind I explain how to work it in correctly and how much oil to use at a time roughly
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=332751#p332751 said:
thudpucker » 22 Oct 2013, 22:48[/url]"]Do us all a Favor and fill out your profile. It helps us with answers. Plus there might be one of us close by... :LOL2:
Sorry bout that. Updated :mrgreen: :mrgreen:
 
Disconnect the spark plugs.
Remove the spark plugs.
Spray in above mentioned oil.
Slowly crank over motor.
Note resistance
Report back
 
Also make sure it is in water or on the muffs before you try and start it. If your slowly turning it over your water pump should survive.

And on that note I'd be ready to put a new impeller in the lower unit and replace the lower unit oil.
 
I’m a bit confused,

Your post subject says “1975 mercury 200 hard to pull” I would think so............. :LOL2:

I don’t know of too many 200HP that you pull start. Is that a typo? Never the less it’s not going hurt to pull the plugs and spray a light coat of Marvel mystery oil or alike in the cylinders.
Let it sit for a while and slowly turn the motor over by hand, and by hand I mean don’t use the starter. This way if there is resistance you will feel it and can stop.

If you force it you’re going to F something up. Use a breaker bar with a socket on the top of the flywheel.
Again you shouldn’t feel any resistance because the plugs are out and you’re not building compression.
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=332767#p332767 said:
Country Dave » Today, 08:30[/url]"]I’m a bit confused,

Your post subject says “1975 mercury 200 hard to pull” I would think so............. :LOL2:

I don’t know of too many 200HP that you pull start. Is that a typo? Never the less it’s not going hurt to pull the plugs and spray a light coat of Marvel mystery oil or alike in the cylinders.
Let it sit for a while and slowly turn the motor over by hand, and by hand I mean don’t use the starter. This way if there is resistance you will feel it and can stop.

If you force it you’re going to F something up. Use a breaker bar with a socket on the top of the flywheel.
Again you shouldn’t feel any resistance because the plugs are out and you’re not building compression.


The Merc 200 was a 20hp motor. Sheesh Dave!
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=332777#p332777 said:
Lowe 2070 CC » 20 minutes ago[/url]"]
[url=https://www.tinboats.net/forum/viewtopic.php?p=332767#p332767 said:
Country Dave » Today, 08:30[/url]"]I’m a bit confused,

Your post subject says “1975 mercury 200 hard to pull” I would think so............. :LOL2:

I don’t know of too many 200HP that you pull start. Is that a typo? Never the less it’s not going hurt to pull the plugs and spray a light coat of Marvel mystery oil or alike in the cylinders.
Let it sit for a while and slowly turn the motor over by hand, and by hand I mean don’t use the starter. This way if there is resistance you will feel it and can stop.

If you force it you’re going to F something up. Use a breaker bar with a socket on the top of the flywheel.
Again you shouldn’t feel any resistance because the plugs are out and you’re not building compression.



The Merc 200 was a 20hp motor. Sheesh Dave!


LOL Hey thanks for clearing that up bro, I'm not an old Merc guy.
 
My first boat was a 14' Crestliner with a Merc 200 20hp of the same vintage. Motor ran like a top, but it pulled hard, and I was a whole lot younger then :LOL2: :LOL2: It was the reason that all my boats since that one have had electric start :LOL2:
 
It is a 20hp , I should of clarified that. I replaced the plugs already, old ones were a little black but not bad, after I replace the impeller this weekend, I will work the oil in. I did pick up a carb kit, but I want want to see how everything sounds before I go and start replacing things. Thanks for all the help and advice. I will be restoring a 13.4 Gregor in the near future. I'll get some pics up
 
Oh, and I will be picking up a compression tester from autozone to check that as well. $40 deposit and then full money back when returned
 

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